By Doug Macron
As Tekmira Pharmaceuticals this week released its third-quarter financial results, the company's top official provided an update on the firm's research-and-development efforts, stating that it's on track to report phase I data on its lead cancer drug by year end and begin human trials of an Ebola treatment in early 2012.
Tekmira President and CEO Mark Murray also reaffirmed the company's commitment to a trade secret-misappropriation lawsuit it filed against partner Alnylam Pharmaceuticals. While he didn't comment in detail on the case, his remarks during a conference call indicate that the two RNAi drug developers remain firmly at odds over the rights to their siRNA delivery technologies.
Currently, Tekmira has one clinical-stage drug, the polo-like kinase 1-targeting cancer treatment TKM-PLK1. In January, the company moved the agent into a phase I open-label, multi-dose, dose-escalating study in up to 52 patients with advanced solid tumors.
This summer, US regulators cleared Tekmira to begin another phase I trial of the drug in collaboration with the National Cancer Institute. That study is examining TKM-PLK1 in patients with either primary liver cancer or liver metastases.
According to Murray, the trials are expected to help Tekmira develop a data package that will guide the design of future clinical studies of the drug. During the call, he added that the company “anticipate[s] reporting interim data from both of these trials in the next few months.”
On deck in the company's pipeline is TKM-Ebola, an siRNA-based treatment for Ebola infection under development with support from the US Department of Defense Chemical and Biological Defense Program, which could fund the drug's development through commercialization (GSN 8/19/2010).
Murray said that Tekmira has now completed investigational new drug application-supporting preclinical work for TKM-Ebola, and that it is positioned to file the IND by the end of 2011. The company expects to begin a phase I trial in the first quarter of next year.
He also touted the improvements Tekmira has made in its manufacturing capabilities as it advances the Ebola drug, reiterating statements from earlier in the year that the company has scaled up its siRNA-manufacturing process from 10-gram batches to 1-kilogram batches.
He said in August that Tekmira was aiming to move its capabilities up to 5 kilograms, but this week he did not provide any update on that effort.
Tekmira's stalled hypercholesterolemia drug candidate TKM-ApoB, meantime, has been put back in the queue along with various other early-stage preclinical candidates the company is considering for further development, Murray indicated.
The drug, which is designed to silence apolipoprotein B, was Tekmira's first to reach human testing. However, in early 2010 a phase I trial of the agent was placed on hold after a patient experienced side effects the company said were consistent with siRNA-related immune stimulation (GSN 1/14/2010).
Efforts to restart the program ran aground amid disappointing preclinical performance by additional siRNA sequences, and Tekmira has kept the program on the back burner.
This week, Murray said that Tekmira is “evaluating a number of new” lipid nanoparticle delivery formulations for the apoB program, but said that “for the moment, we want to focus on [the cancer and Ebola drug candidates] and get those clinical programs properly supported.”
Tekmira will still “look at apoB and the new formulations,” he added, although he indicated that the program would be evaluated in parallel with the “growing pipeline of promising preclinical candidates for which we have generated pivotal animal efficacy data.”
Murray noted that Tekmira has looked at “over 80 molecular targets for RNAi silencing and biological effect,” arriving at a “short list of candidates” that includes targets in metabolic, infectious, and cardiovascular diseases, as well as cancer.
He also said that the firm is “increasingly focused on a combinatorial approach for indications where we believe silencing genes in multiple cellular pathways will result in superior efficacy.”
He did not offer any additional details on future programs or a timeframe for when they would be announced. His comments this week, however, jibe with statements made during Tekmira's second-quarter conference call this summer, when he said that the company has generated preclinical data on a cocktail of siRNAs designed to simultaneously inhibit two cancer targets, WEE1 and CSN5.
During this week's call, Murray also referenced Tekmira's ongoing litigation with Alnylam, stating that “we remain firm in our belief that this lawsuit is necessary for us to recover our technology and retain its full value.”
In March, Tekmira sued Alnylam for allegedly using its trade secrets related to its core lipid nanoparticle, or LNP, delivery technology (GSN 3/17/2011).
Alnylam has denied any wrongdoing and countersued Tekmira for, among other things, violating provisions in the companies' partnership agreements to handle disagreements through “confidential and non-public alternative dispute resolution procedures.”
As the legal wrangling progresses through the court system, each company has staked claim to the disputed technology.
During the conference call, Murray noted that four of Alnylam's drug candidates are “LNP-enabled.” These include the phase I liver cancer drug ALN-VSP and the phase I transthyretin-mediated amyloidosis treatment ALN-TTR01, as well as the preclinical hypercholesterolemia therapy ALN-PCS and a second-generation version of the TTR drug called ALN-TTR02, which is slated to enter human testing next year.
Alnylam publicly states that ALN-VSP and ALN-TTR01 use Tekmira's technology, but it maintains that the delivery systems applied to ALN-PCS and ALN-TTR02 are both proprietary.
Murray confirmed that Tekmira has sought a fall 2012 trial date for the Alnylam litigation.
For the three-month period ended Sept. 30, Tekmira's net loss fell to $1.5 million, or $0.12 a share, from a year-ago loss of $2.4 million, or $0.24 a share.
Revenues in the quarter fell to $4.2 million from $10.4 million a year earlier. However, the revenues recorded in the third quarter of 2010 include a $5.9 million payment related to non-RNAi legacy technology that Tekmira licensed to Talon Therapeutics.
Expenses in the quarter were $4.4 million, down from $5.2 million in the year-ago period, reflecting higher costs associated with manufacturing obligations for Alnylam and staff bonuses paid out in the third quarter of last year.
General and administrative spending in the quarter dipped to $1.2 million from $1.5 million.
At the end of the third quarter, Tekmira had $9.2 million in cash and cash equivalents. Following a $5.1 million financing round in the second quarter and the impact of revenues from collaborative partners, the company said it has enough cash on hand to support its drug-development efforts until the end of 2012.
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